1. Field of the Invention
This invention relates to a door-closer latch that can be set in different degrees of closing of the door selectively by manipulation of the latch mechanism from a location remote from such latch mechanism.
2. Prior Art and Problems Thereof
The general state of the prior art and problems inherent therein are well described in U.S. Pat. No. 3,162,889, issued Dec. 29, 1964, at column 1, lines 18 to 39, as follows:
It is common practice to use a holding clip on the piston rod to maintain the open position of the door. This clip is essentially a ring surrounding the rod, and which engages the end of the cylinder at a point eccentric with respect to the rod axis. This point of engagement is usually determined either by providing a side extension on the clip which extends axially somewhat, or by using an eccentric boss or projection on the end of the cylinder as an abutment. The eccentric forces produce a rotation of the clip on an axis perpendicular to that of the rod, and jam the clip against axial movement. This action is sufficient to block retraction of the rod at the selected clip position. The clip is often set when one wishes to carry an armful of objects into the house, and does not wish to bother with opening the door. PA0 After the clip has performed its function, it is normally restored to the inactive position by moving the door open slightly, and manually slipping the clip along the rod to a point where the door can close fully without engaging the clip. This maneuver is sometimes difficult when one is wearing gloves, and obvious requires a return to the door to attend to this detail. PA0 The L shaped clip 68 is provided with an aperture approximating the cross section of the stock used for the piston rod lever so that it may be slid end wise onto the latter during manufacture. A slight clearance relative to the lever member permits the clip 68 to be slideably positioned along the piston rod part thereof and the unperforated leg of the clip extending toward the end of the cylinder in bearing against the cylinder end cap 51 causes the apertured portion to cant and come into locking edge engagement with the piston rod, thereby holding the piston rod from inward movement into the cylinder to maintain the door at a selected open position. PA0 To hold the associated door member in an open position, I provide stop means in the form of a plate 49 which can be generally oval in shape and carries a grommet 50 of cushioning material adapted to slidably receive piston rod 9. . . . One end 49' of plate 49 is bent toward cylinder 1, and the other end thereof is bent away from the cylinder toward bracket 12, whereby when the door member 15 closes to a point where the inturned end 49' engages cylinder 1, the plate 49, which normally assumes the position shown in broken lines in FIG. 6, will tilt or cant as shown in full lines therein, in a manner such as to bind on rod 9 and hold rod 9 and cylinder 1 against further relative movement. . . . When it is desired to permit the door member to move further toward closed position, plate 49 can be manually grasped and slid along rod 9 to another position. PA0 In door closers employing a coacting cylinder and piston construction and cooperating spring means therefor, it is usual to apply to the piston road a specially formed washer-like element generally known as a "hold-open" washer which is slidably mounted on the piston rod and provided with an offset portion designed to engage that end of the cylinder through which the piston projects as to cause the washer to cant when it receives pressure exerted by the end of the cylinder, thus to bite against the piston rod and therefore when the piston rod has been withdraw from the cylinder to a desired degree, making it possible to hold the door open. PA0 the unit includes a hold-open washer 15 which is offset at 16 and 17 as a means for causing the washer to cant when positioned adjacent to the end 18 of the cylinder 10 to engage the piston rod 11 in biting engagement and restrain it from movement farther into the cylinder 10, when it is caused to project to a predetermined degree from the cylinder. PA0 The door to which my assembly is applied may be temporarily held in the open or partially open position by sliding the oversize washer 52 against the stud 53 projecting from the cap 21a, with the door in the position sought to be maintained. PA0 The closing biasing influence of the spring 35 is rendered inoperative to close the door by reason of the frictional canting and wedging of the washer 52 against the rod 19, caused by the pressure of the stud 53 against the washer 52. Release of the door is accomplished by further opening the door and thereafter sliding the washer away from the piston end of the rod 19. PA0 The prior art hold-open means generally employed in spring loaded door closing door checks of the class hereinabove described have proved to be unsatisfactory because of the difficulties involved in making them operative to hold the door open and the inconvenience of releasing the hold-open means to release the door closing door checks for normal operation. PA0 The manually engageable quick release means 30 of the invention is preferably incorporated on the outer end of the said cylinder head 23. PA0 The short or stop end of the lever latch 31 is preferably bent to form a stop 311 which is of the correct length to hold the said lever latch 31 parallel to the outer end 231 of the cylinder head 23 when the said lever latch is rotated about the pivot pin 32 clockwise as viewed in FIG. 2. The long or operating end of the lever latch 31 is provided with an aperture 312 therethrough slightly larger in diameter than the diameter of the piston rod 22 so that the said piston rod 22 is free to reciprocate through the lever latch 31 when it is disposed in an unlatched position parallel to the outer end 231 of the cylinder head 23, see FIG. 2. The said long or operting end of the lever latch 31 extends a sufficient distance outwardly of the piston rod 22 to provide an operating tab 313. PA0 A spring loaded plunger 35 is reciprocatingly mounted in a suitable bore 233 in the cylinder head 23 below the lever latch 31 inwardly of the operating tab 313 thereof, which spring loaded plunger constantly urges the lever latch 31 to pivot clockwise as viewed in FIG. 1 to its unlatched position shown in FIG. 2. Thus, the lever latch 31 is normally disposed in its unlatched position shown in FIG. 2. . . . PA0 Accordingly, the door 11 may be releasably held in a partially open or substantially fully open position by the manually set quick release hold-open means 30 by the simple expedient of pressing the operating tab 313 of the hold-open lever latch 31 and releasing the door for closing by the door closing door check 10 while maintaining pressure on the said pressure tab 313. The hold-open means 30 immediately makes the door closing door check 10 inoperative until the hold-open lever latch 31 is released by manually pushing the door 11 ever-so-slightly toward its fully open position. PA0 Applicant has provided a device for automatically moving the holding clip to inactive position simply in response to a slight push on the door to a more fully-opened position, with the added movement of the door being just sufficient to release the pressure between the end of the cylinder and the clip. Essentially, the performance of the device is based on the application of a continuing biasing force which is applied centrally on the clip, but of a sufficiently weak nature to be readily overcome by the eccentric jamming forces. As soon as these jamming forces are released by a slight initial opening movement of the door, however, the light central biasing forces proceed to produce a smooth axial movement of the clip along the rod ahead of the cylinder as the door moves to the closed position. PA0 The door may be held in a fully or partially opened position by the use of the holding clip 17. This clip is essentially a washer surrounding the piston rod 11, with the extension 18 formed to engage the end 19 of the cylinder at a point eccentric from the axis of the rod 11. If the clip 17 is placed in a particular position along the rod when the door is open, and the door is then released, the first engagement with the clip 17 with the end 19 of the cylinder takes place at the extension 18. The forces at this point result in the generation of a moment which rotates the clip on an axis perpendicular to that of the rod. A jamming action thus develops which prevents axial movement along the rod. . . . PA0 As soon as the door is pushed a little further open from the position shown in FIG. 1, however, the jamming forces are released. The compressed spring 20 is therefore free to apply relatively central forces to the clip 17, and to produce a movement of the clip along the rod 11 to the left as shown in FIGS. 1 and 2 toward the bracket 15. . . . The spring 20 therefore pushes the clip ahead of it as the closing of the door proceeds. PA0 a slight opening movement of the door will result in the release of the forces applied to the extension 18, so that the resilience of compression of the washer 21 can move the clip 17 toward the bracket 15 without the generation of a jamming action. The setting of both the device shown in FIGS. 1 and 2 and that in FIG. 3 requires that a slight degree of manual force be applied to the clip to set the open position of the door, and compress the resilient member enough to bring the extension 18 into engagement with the cylinder end 19. PA0 Releasable latches presently known allow a door to be held fully open. . . . However such devices do not provide an auxiliary mechanism which will enable a door to be held in any selected intermediate or partially open position. PA0 When door 90 is opened, cylinder 20 moves in the direction of arrow 102 as seen in FIG. 5. When cord 100 becomes taut, block 24 is pulled in the direction of arrow 104 within bracket 16 against the action of spring 36 causing follower 64 to move out of recess 58. Because of the configuration of spring member 14, follower 64 is biased to move in the direction of arrow 106 against side flange 53 adjacent ramp 60. During the opening of door 90, lever 70 slides along piston rod 23. PA0 On the release of door 90 to allow it to begin to move towards a re-closed position, cylinder 20 moves in the direction of arrow 108 as seen in FIG. 6, loosening cord 100 and allowing spring 36 to push block 24 in the direction of arrow 110 within bracket 16. . . . At the same time lever 70 is tilted, in the plane of piston rod 23, in the direction of arrow 112 by the movement of rod 28 and locks against piston rod 23 to prevent the door from closing. In this setting, door 90 will be held slightly less than fully open and spring 36 will be relatively uncompressed. However, spring 36 is not fully extended when lever 70 is locked on piston rod 23, thus imparting an additional force on the lever to maintain it in the locked position. PA0 To release door 90 from the position of FIG. 6 and allow it to close, lever arm 76 is depressed in the direction of arrow 114 as seen in FIG. 7, which releases lever 70 from locking engagement with piston rod 23 and allows the lever to slide along the piston rod, permitting the piston to move in relation to cylinder 20. Also the depression of lever arm 76 moves rod 28 in the direction of arrow 116 to fully depress spring 36 (as in FIG. 5) and move block 34 in the direction of arrow 118, causing follower 64 to move along inclined leading edge 54 of shoulder 52 in the direction of arrow 120. Because of the bias of follower 64 it returns to its position of rest in recess 58 in trailing edge 56 of shoulder 50. Shoulder 52 ensures that follower 64 does not overshoot recess 58 on the return to its position of rest. PA0 Alternatively, door 90 may be released from the open position by opening the door fully, from the slightly less than fully open position of FIG. 6, which will release lever 70 from locking engagement with piston rod 23, as in FIG. 5. As a further alternative, the release of door 90 from the position of FIG. 6 may be effected by pushing knob 48 to move rod 28 and release lever 70 from locking engagement with piston 92.
Clips of this general type are disclosed in the following patents:
U.S. Pat. No. 2,808,608, issued Oct. 8, 1957, shows a door check having a latch described as follows at column 3, lines 42 to 55:
The open position is selected by sliding of the clip 68 into the desired position along the piston rod, which sliding must be accomplished manually.
U.S. Pat. No. 2,930,070, issued Mar. 29, 1960, describes a door-closer latch at column 4, lines 49 to 74, as follows:
Thus, the position at which the door member is to be held is selected by manually grasping the plate 49 and shifting it along the rod 9.
U.S. Pat. No. 3,032,806, issued May 8, 1962, describes the prior art at column 1, lines 11 to 22, as follows:
The hold-open washer of that patent is described more particularly at column 2, lines 45 to 51, as follows:
No mechanism is disclosed for positioning the washer adjacent to the end 18 of the cylinder 10, indicating that manual positioning is relied upon.
In U.S. Pat. No. 2,940,111, issued June 14, 1960, a door-closer latch is described at column 4, lines 22 to 33, as follows:
No mechanism is shown or described for sliding the washer against the stud or sliding the washer away from the cylinder end so that, again, such sliding presumably can only be effected manually.
U.S. Pat. No. 3,105,264, issued Oct. 1, 1963, discloses latch mechanism for a door-closing door check at column 1, lines 26 to 32, as follows:
This patent then describes its latch at column 2, lines 32 to 34:
The release means is then described in detail at column 3, line 7, to column 4, line 2, as follows:
The latch of this patent must be set manually by pressing tab 313 and then manually maintaining pressure on the tab 313 to render the door check inoperative until the lever latch 31 is later released by opening movement of the door.
Presumably, U.S. Pat. No. 3,162,889 was describing in the excerpt quoted above deficiencies of the door-closer latches shown in these various earlier patents. The latch of U.S. Pat. No. 3,162,889 also, however, was required to be set manually, although it could be released simply by opening the door slightly, as in the case of U.S. Pat. No. 3,105,264 discussed above. Pat. No. 3,162,889 describes its improvement at column 1, lines 39 to 53:
Although the clip can be released from latched position automatically, it still must be set in a particular latched position manually, as indicated in the description at column 2, lines 7 to 63:
Despite the fact that the latch can be released automatically by slightly opening the door it is still necessary to apply manual force to the clip to set the door-closer latch for holding the door in a particular selected position.
A more complicated latch arrangement is disclosed in the much later U.S. Pat. No. 4,194,264, issued Mar. 25, 1980, which patent states at column 1, lines 11 to 17:
This latter statement is incorrect because the latch devices disclosed in U.S. Pat. Nos. 2,808,608; 2,930,070; 3,032,806; 2,940,111; 3,105,264; and 3,162,889 discussed above can latch door-closer mechanism to hold doors in various selected partially opened positions. It appears that the mechanism disclosed in Pat. No. 4,194,264 does not have that capability.
On the contrary, the latch mechanism of Pat. No. 4,194,264 can latch closer mechanism to hold the door in only one, slightly less than fully open position, as stated in column 3, lines 17 to 67:
Thus, while the mechanism shown in U.S. Pat. No. 4,194,264 can be latched in one preselected position depending upon the length of cord 100, there does not appear to be any suggestion for latching the closer mechanism to hold the door in different selected, partially open positions.
The problem of previous door-closer latches of the tilting latch plate type to which the present invention relates are principally two. The first problem is that, as discussed with respect to the patents other than U.S. Pat. No. 4,194,264, the latch mechanism must be set manually by directly manipulating the latch plate. Such requirement is not a particular disadvantage when the door closer is mounted elevationally near the center of the door, as shown in FIG. 5 of U.S. Pat. No. 3,105,264, but the problem is greatly aggravated when the door closer is mounted at the top of the door as shown in FIG. 1 of U.S. Pat. No. 2,940,111, as it frequently is.
The second problem is that, even if the door-closer latch mechanism can be set automatically, as disclosed in U.S. Pat. No. 4,194,264, such latch mechanism is deficient if it cannot enable the door-closer mechanism to be latched with the door in different selected degrees of opening. When a person desires to carry an arm full of objects into the house and does not wish to bother with opening the door, as discussed in U.S. Pat. No. 3,162,889, as quoted above, the door closer may be latched with the door in substantially fully open position. It may, however, be desirable to latch the door closer for holding the door in only slightly open position such, for example, as to enable a cat or a dog to have ingress to and egress from the building while having the door closed as far as possible.